There is some strange thing in the way how the setFromObject method works. What is a reason to not have the strict box size here?
Computes the world-axis-aligned bounding box of an Object3D (including its children), accounting for the object’s, and children’s, world transforms. The function may result in a larger box than strictly necessary.
The function may result in a larger box than strictly necessary. - Really? May result and may not result as we wish… Is it depend on the weather outside?